Research On Virtual Design System Of Planar Controlled Lower-pair Five-bar Mechanism

With the development of computer technology and control technology, contemporary mechanism shift from the area of single-degree to the complex multi-degree domain. As the simplest multi- degree mechanism, the controlled five-bar mechanisms are becoming the hot spot area of mechanism.Starting with the structure of the planar controlled five-bar mechanism, this thesis has discussed the motion regularity of the 13 basic types of five-bar mechanism. And on this foundation, a virtual visualization design system of five-bar is developed with the technical superiority of Visual C++ in the visualization aspect combined with OpenGL platform.First, the constructive principle of basic types composed of similar Class II groups is introduced, and then the motion models of every similar Class II groups are set up. Based on this, this thesis presents the method of motion analysis of five-bar mechanism. The successful utilization of "two-step synthesis" method in track synthesis of RRRPR basic type offers theoretical basic for other basic type of five-bar mechanism.The independence, openness and cross-platform make OpenGL become the powerful tool in development of three-dimensional virtual system. Five three-dimensional models of five-bar parts are created through studying the five-bar structure to realize the parameterization of five-bar mechanism. The study of incompatibility technology in OpenGL resolves the poor incompatibility using mouse, and enhances the operation of system.The system developed by united programming of VC++ and OpenGL realizes two main functions of motion analysis and track synthesis. Through setting the parameters of five-bar and the interactive selection of tack point, the mechanism dynamic simulation and real-time analysis of the generated path can be achieved, including the output of displacement, velocity, acceleration and relevant information, so the system has a high comprehensiveness. The introduce of genetic algorithm resolves the multi-peak problem in track analysis of five-bar, and the result check in the end achieve the unification of motion analysis and track synthesis.This virtual design system has a beautiful, compact interface, strong interactive and a high practical value. It offers the experimental conditions for the motion analysis and the accurate path generation of controlled five-bar, and the reference for the further dynamics analysis and optimization of compensating motion.